Investigating miRNA signatures in metastatic breast cancer: An in silico analysis.

miRNAs are small non-coding RNAs that regulate most cellular processes. Tumorigenesis disrupts the normal balance in the cell, which leads to changes in the cell cycle, cell signalling, activation of growth factors, miRNA deregulation, etc. Thus, the variations in miRNA expression between normal and tumor stages can be used to predict, diagnose, detect and identify different cancer stages, thereby suggesting the potential use of the miRNAs as biomarkers or potential therapeutic targets for cancer. In this study we aim to identify differentially expressed miRNAs which could serve as potential biomarkers or therapeutic targets for breast cancer. Microarray-based expression analysis was performed on tissue samples from patients with early and locally advanced breast cancer and nCounter analysis was performed to detect differentially expressed miRNA. Additionally, functional enrichment analysis, miRNA linked gene prediction, and in silico analysis for miRNA expression in cancer databases were carried out. This analysis revealed increased expression of Hsa-miR-199a and b. Further these miRs had increased expression levels across various cancer. Importantly, genes such as CALR, SSR2, and YWHAZ predicted as miRs target were highly expressed in breast cancer. However, these genes lack therapeutic drugs targeting them. Overall, our study identified previously unexplored miRNAs and their gene targets, which could be exploited as potential targets for future therapeutic interventions.